Lipoprotein(a): Role in atherosclerosis and new treatment options.

Atherosclerosis is a chronic process characterized by inflammation and the progressive accumulation of inflammatory cells and lipids in the blood vessel wall, resulting in narrowing of the blood vessel's circumference. Treatment of people with dyslipidemia aims to reduce the risk of developing atherosclerotic disease and prevent major adverse cardiovascular events (MACE). The results of previous studies indicated that lipoprotein(a) (Lp(a)) is a critical causal factor in the estimated risk of developing a cardiovascular (CV) incident even after achieving desirable low-density lipoprotein (LDL) cholesterol levels. Lp(a) is a low-density lipoprotein particle, like LDL cholesterol. The levels of Lp(a) in plasma are genetically determined. Lp(a) catabolism is still controversial. The pathogenic potential of Lp(a) can be divided into three categories: promotion of plaque formation, thrombogenicity, and proinflammatory effects. Lp(a) levels above the 75th percentile reduced the risk of aortic valve stenosis and myocardial infarction, whereas higher levels (above 90th percentile) were associated with an increased risk of heart failure. However, no hypolipidemic agents have been approved for targeted use in patients with high Lp(a) levels. There are insufficient randomized controlled trials assessing CV outcomes that would support the evidence that current treatment options, which effectively lower Lp(a) levels, also effectively prevent CV event. However, according to some studies, there is strong evidence that better CV outcome is one of the benefits of such therapy. The results of ongoing clinical trials are eagerly awaited.

Association of androgenetic alopecia with a more severe form of COVID-19 infection.

BACKGROUND: Individual susceptibility to develop acute respiratory distress syndrome is related to age and most frequent comorbidities. So far, it is known that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) primarily infects the type II pneumocytes in humans, with the help of transmembrane serine protease type 2 (TMPRSS2). Up to now, the only known transcriptional promoters of genes coding TMPRSS2 are androgenic. Theoretically, the elevated level of androgens or androgen receptors would lead to a higher expression of TMPRSS2 and a higher level of viremia as a consequence. AIM: The aim of our research was to indirectly investigate if the severity of SARS-CoV-2 infection is dependent on the expression of androgen receptors. METHODS: This observational study analysed male patients hospitalized for SARS-CoV-2 infection with respect to the length of hospitalisation, the outcome of the disease, the type of necessary oxygen support and the presence of comorbidities and hairiness. In hairiness estimation, we used an adapted version of the Hamilton-Norwood scale and the presence of the Gabrin sign. RESULTS: In total, 208 patients were enrolled in the study. There were statistically significant differences comparing the average age of patients with the different types of alopecia when groups were divided according to the presence of the Gabrin sign (t = 4.958, p > 0.01). The outcomes and the type of needed minimal oxygen support, compared with the type of alopecia in the case of Gabrin + / - classification showed a statistically significant difference in the outcome of the disease (p = 0.027). There were no statistically significant differences in the distribution of comorbidities among alopecia groups, but hypertension was related to poor COVID-19 prognosis. CONCLUSION: Our findings suggest that the Gabrin sign and hypertension are related to a poor COVID-19 prognosis.

The Association Between Brain Volumes and Posttraumatic Stress Disorder in Intensive Care Unit Survivors: A Preliminary Study.

INTRODUCTION: Millions of Americans are admitted to the intensive care unit (ICU) per year. Many survivors of the ICU will experience posttraumatic stress disorder (PTSD); although volumetric hippocampal and amygdala studies have been conducted in other trauma survivors (i.e., veterans), the association between PTSD symptoms and hippocampal and amygdala volumes in ICU survivors has not been described. We hypothesize that the severity of posttraumatic stress symptoms in ICU survivors is associated with lower volumes of both the hippocampus and amygdala at 3 and 12 months. METHODS: Secondary analysis of the VISIONS study, a prospective sub-study of the BRAIN-ICU cohort, which included survivors of critical illness. The PTSD Checklist Specific was used at 3 and 12 months to evaluate the ICU as a traumatic experience. A Philips Achieva 3T MRI scanner was used to scan patients at both discharge and 3 months. To compare median brain volumes at discharge and 3 months for those with and without PTSD symptomatology, we used a Kruskal-Wallis (KW) test. RESULTS: At 3 month follow up, three patients had PTSD symptomatology and N = 1 at 12 month follow up. There was no difference between median brain volumes (hippocampus or amygdala) between individuals with PTSD symptomatology at either 3 or 12 months (p-values > 0.05). DISCUSSION: Although our study did not reveal significant differences in brain volumes between PTSD patients and non-PTSD patients, sample size was a major limitation and larger scale studies should be undertaken to elucidate possible neurobiological markers of PTSD in ICU survivors.

Glial scars are permeable to the neurotoxic environment of chronic stroke infarcts.

Following stroke, the damaged tissue undergoes liquefactive necrosis, a stage of infarct resolution that lasts for months although the exact length of time is currently unknown. One method of repair involves reactive astrocytes and microglia forming a glial scar to compartmentalize the area of liquefactive necrosis from the rest of the brain. The formation of the glial scar is a critical component of the healing response to stroke, as well as other central nervous system (CNS) injuries. The goal of this study was to evaluate the toxicity of the extracellular fluid present in areas of liquefactive necrosis and determine how effectively it is segregated from the remainder of the brain. To accomplish this goal, we used a mouse model of stroke in conjunction with an extracellular fluid toxicity assay, fluorescent and electron microscopy, immunostaining, tracer injections into the infarct, and multiplex immunoassays. We confirmed that the extracellular fluid present in areas of liquefactive necrosis following stroke is toxic to primary cortical and hippocampal neurons for at least 7 weeks following stroke, and discovered that although glial scars are robust physical and endocytic barriers, they are nevertheless permeable. We found that molecules present in the area of liquefactive necrosis can leak across the glial scar and are removed by a combination of paravascular clearance and microglial endocytosis in the adjacent tissue. Despite these mechanisms, there is delayed atrophy, cytotoxic edema, and neuron loss in regions adjacent to the infarct for weeks following stroke. These findings suggest that one mechanism of neurodegeneration following stroke is the failure of glial scars to impermeably segregate areas of liquefactive necrosis from surviving brain tissue.

Multiplex immunoassay characterization and species comparison of inflammation in acute and non-acute ischemic infarcts in human and mouse brain tissue.

This study provides a parallel characterization of the cytokine and chemokine response to stroke in the human and mouse brain at different stages of infarct resolution. The study goal was to address the hypothesis that chronic inflammation may contribute to stroke-related dementia. We used C57BL/6 and BALB/c mice to control for strain related differences in the mouse immune response. Our data indicate that in both mouse strains, and humans, there is increased granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin-6 (IL-6), interleukin-12 p70 (IL-12p70), interferon gamma-induced protein-10 (IP-10), keratinocyte chemoattractant/interleukin-8 (KC/IL-8), monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), macrophage inflammatory protein-1ß (MIP-1ß), regulated on activation, normal T cell expressed and secreted (RANTES), and Tumor necrosis factor-α (TNF-α) in the infarct core during the acute time period. Nevertheless, correlation and two-way ANOVA analyses reveal that despite this substantial overlap between species, there are still significant differences, particularly in the regulation of granulocyte colony-stimulating factor (G-CSF), which is increased in mice but not in humans. In the weeks after stroke, during the stage of liquefactive necrosis, there is significant resolution of the inflammatory response to stroke within the infarct. However, CD68+ macrophages remain present, and levels of IL-6 and MCP-1 remain chronically elevated in infarcts from both mice and humans. Furthermore, there is a chronic T cell response within the infarct in both species. This response is differentially polarized towards a T helper 1 (Th1) response in C57BL/6 mice, and a T helper 2 (Th2) response in BALB/c mice, suggesting that the chronic inflammatory response to stroke may follow a different trajectory in different patients. To control for the fact that the average age of the patients used in this study was 80 years, they were of both sexes, and many had suffered from multiple strokes, we also present findings that reveal how the chronic inflammatory response to stroke is impacted by age, sex, and multiple strokes in mice. Our data indicate that the chronic cytokine and chemokine response to stroke is not substantially altered in 18-month old compared to 3-month old C57BL/6 mice, although T cell infiltration is attenuated. We found a significant correlation in the chronic cytokine response to stroke in males and females. However, the chronic cytokine response to stroke was mildly exacerbated by a recurrent stroke in both C57BL/6 and BALB/c mice.